scholarly journals statSuma: automated selection and performance of statistical comparisons for microbiome studies

2021 ◽  
Author(s):  
Robert J. Leigh ◽  
Richard A. Murphy ◽  
Fiona Walsh
Keyword(s):  
Statistical Tests ◽  
Data Distribution ◽  
Small Sample ◽  
Statistical Procedure ◽  
T Test ◽  
Desktop Computer ◽  
And Performance ◽  
Student’S T ◽  
Small Sample Sizes ◽  
Student’S T Test

There is a reproducibility crisis in scientific studies. Some of these crises arise from incorrect application of statistical tests to data that follow inappropriate distributions, have inconsistent equivariance, or have very small sample sizes. As determining which test is most appropriate for all data in a multicategorical study (such as comparing taxa between sites in microbiome studies), we present statsSuma, an interactive Python notebook (which can be run from any desktop computer using the Google Colaboratory web service) and does not require a user to have any programming experience. This software assesses underlying data structures in a given dataset to advise what pairwise or listwise statistical procedure would be best suited for all data. As some users may be interested in further mining specific trends, statSuma performs 5 different two-tailed pairwise tests (Student's t-test, Welch's t-test, Mann-Whitney U-test, Brunner-Munzel test, and a pairwise Kruskal-Wallis H-test) and advises the best test for each comparison. This software also advises whether ANOVA or a multicategorical Kruskal-Wallis H-test is most appropriate for a given dataset and performs both procedures. A data distribution-vs-Gaussian distribution plot is produced for each taxon at each site and a variance plot between all combinations of 2 taxa at each site are produced so Gaussian tests and variance tests can be visually confirmed alongside associated statistical determinants.

Commonly used measures and statistical tests.

2021 ◽  
pp. 103-118
Author(s):  
Donald L. J. Quicke ◽  
Buntika A. Butcher ◽  
Rachel A. Kruft Welton
Keyword(s):  
Statistical Tests ◽  
T Test ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Fisher’S Exact Test ◽  
Chi Squared ◽  
Student’S T ◽  
Student’S T Test

Abstract There are a number of statistical tests that are frequently used, even by non-specialists. This chapter will cover tests such as Chi-squared, Fisher's exact test, Mann-Whitney U and several variations of the Student's t-test, amongst others.

scholarly journals Duality CEO-Chairman and its relation with the effectiveness of the board control

2019 ◽  
Vol 17 (4) ◽  
pp. 239-251 ◽  
Author(s):  
Cesar Freire
Keyword(s):  
Statistical Tests ◽  
Simultaneous Equations ◽  
Independent Directors ◽  
Chi Square ◽  
Good Corporate Governance ◽  
And Performance ◽  
Student’S T ◽  
Secondary Information ◽  
Student’S T Test ◽  
Risk Supervision

The study focused on analyzing the duality CEO-Chairman and its relation on the effectiveness of the board control. A sample of 347 companies with annual sales volume greater than five million US dollars was selected; a questionnaire was provided in order to measure the effectiveness of the board control. To measure the duality CEO-Chairman secondary information was used, and verification was made about the existence of the duality. The effectiveness of the board was measured by an index obtained through the use of confirmatory factorial analysis. Statistical tests were performed, such as Student’s t-test for mean difference, Chi-square to measure the dependence and regression by simultaneous equations to answer the questions. As a result, it was found out that the duality CEO-Chairman is connected in a significant way with the performance of independent directors and risk supervision of the board. The results regarding the duality relationship CEO-Chairman and performance of independent directors are shown to be inverse, while with risk supervision it becomes direct. The obtained results theoretically contribute to the knowledge regarding the practices of good corporate governance.

scholarly journals Nurses' leadership styles in the icu: association with personal and professional profile and workload

2009 ◽  
Vol 17 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Alexandre Pazetto Balsanelli ◽  
Isabel Cristina Kowal Olm Cunha ◽  
Iveth Yamaguchi Whitaker
Keyword(s):  
Leadership Styles ◽  
Leadership Style ◽  
T Test ◽  
Descriptive Statistics ◽  
Nursing Workload ◽  
Comparison Test ◽  
Multiple Comparison Test ◽  
Professional Profile ◽  
Student’S T ◽  
Student’S T Test

This study aims to explore the association between nurses' leadership styles and personal and professional nursing profile and workload. The sample consisted of seven nurses and seven nursing technicians who were grouped into pairs. At the end of three months, nurses were queried regarding what leadership style would be adopted when the nursing technician under their evaluation delivered care to patients admitted to the ICU. Relevant data was analyzed by applying descriptive statistics, Tukey's multiple comparison test and Student's t-test (p< 0.05). Nursing workload reached 80.1% on average. The personal and professional profile variables did not show any relation with the leadership styles chosen by nurses (p>0.05). The determine, persuade, and share leadership styles prevailed. However, whenever the nursing workload peaked, the determine and persuade styles were used (p<0.05).

scholarly journals Intravesical prostaglandin e2 effectiveness in the prevention of urinary retention after transvaginal reconstruction of the pubo-cervical fascia and short arm sling according to Lahodny: a prospective randomized clinical trial

2010 ◽  
Vol 14 (1) ◽  
pp. 15 ◽  
Author(s):  
G. QUADRI ◽  
N. NATALE ◽  
C. SPREAFICO ◽  
C. BELLONI ◽  
D. BARISANI ◽  
...  
Keyword(s):  
Prostaglandin E2 ◽  
Urinary Retention ◽  
Study Groups ◽  
T Test ◽  
Control Group ◽  
Fisher Exact Test ◽  
Test Results ◽  
Exact Test ◽  
Student’S T ◽  
Student’S T Test

Intravesical prostaglandin E2 is effective in the recovery of spontaneous voiding after transvaginal reconstruction of the pubocervical fascia and short arm sling according to Lahodny. The aim of the study was to compare the effects of intravesical prostaglandin E2 in the prevention of urinary retention after transvaginal reconstruction of the pubocervical fascia and short arm sling according to Lahodny. STUDY DESIGN: From November 1996 to June 1999 fifty women underwent the Lahodny procedure for moderate/severe cystocele and stress urinary incontinence. Women were randomly assigned to 1 of the 2 study groups: intravesical prostaglandin E2 versus controls. Data obtained were analyzed with the Student t test and the Fisher exact test. RESULTS: Two patients of the treatment group had to be excluded from the study, one because of the wrong measurement of the post-voidal residual volume and another due to a fastidious burning sensation which appeared immediately after prostaglandin instillation and required the suspension of the treatment. No other side effects such as nausea, vomiting, diarrhea or hyperthermia were observed. Patients who underwent the prostaglandin E2 treatment showed a recovery of spontaneous voiding after 7.9&plusmn;6.7 days, whereas this interval was significantly longer in the control group, being 12.9&plusmn;9.7 days (p=0.04, Two tailed Unpaired Student's T test). CONCLUSION: The effectiveness and the low associated morbidity mark the treatment with intravesical prostaglandin E2 useful in the recovery of normal voiding after transvaginal pubocervical fascia reconstruction and short arm sling with the procedure according to Lahodny.

scholarly journals Study of Relationship of Anemia among Edentulous Patients

2018 ◽  
Vol 5 (2) ◽  
pp. 105-108
Author(s):  
Lijo Isaac ◽  
A. P. Nirmal Raj ◽  
Reshma Karkera ◽  
R Naveen Reddy
Keyword(s):  
Nutritional Status ◽  
T Test ◽  
Dental Status ◽  
Adult Patients ◽  
Control Group ◽  
Age Group ◽  
Edentulous Patients ◽  
Student’S T ◽  
Relationship Of ◽  
Student’S T Test

Very little studies were done on relationship of the dental status and the nutritional status. The present study was done to study relation between edentulism and the presence of anemia. The study was included of 46 adult patients with edentulism and same numbers of patients were taken as controls. The results were tabulated and analyzed with the help of IBM SPSS statistics 20 using student’s t test. The hemoglobin levels were lower in the edentulous patients that that of the control group. The present study had shown that the nutritional status were poor resulting in anemia in case of edentulous patients as compared to control group with the same age group.  

scholarly journals The influence of proteinuria on tubular transport of Na+, K+, CL

2002 ◽  
Vol 130 (3-4) ◽  
pp. 64-67
Author(s):  
Dejan Petrovic ◽  
Radmila Obrenovic ◽  
Mileta Poskurica ◽  
Biljana Stojimirovic
Keyword(s):  
Statistical Analysis ◽  
Creatinine Clearance ◽  
Significant Influence ◽  
Fractional Excretion ◽  
T Test ◽  
The Third ◽  
Tubular Transport ◽  
Student’S T ◽  
Student’S T Test

Functional and structural damages of tubulointerstitium are caused by proteinuria. The aim of this study was to assess the influence of different proteinuria levels on Na+, K+, Cl tubular transport. We examined 50 patients (24 males, 26 females), mean age 46.50 ? 13.08 years, with mean creati-nine clearence of 87.29 ? 31.17 mL/min. They were separated in three groups depending on proteinuria value. The first group with proteinuria less than 0.3 g/24h included 19 persons (7 males, 12 females), mean age 45.12 ? 13.28 years, with mean creatinine clearance of 94.27 ? 34.70 mL/min. The second group of 18 patients (8 males, 10 females), mean age 45.39 ? 12.64 years had proteinuria of 0.3-3,0 g/24h and mean creatinine clearance of 90.07 ? 31.89 mL/min. The third group had proteinuria level higher than 3.0g/24h and mean creatinine clearance of 73.25 ? 20.44 mL/min. It included 13 patients (9 males, 4 females), mean age 50.08 ? 13.73 years. As a parameter of proteinuria influence on tubular transport of Na+, K+ and Cl-, fractional excretion of these electrolytes, was studied. Student's T test, Mann Whitney U test and c2 test were used for statistical analysis. No statistically significant influence of proteinuria was found on Na+, K+ and Cl tubular transport.

scholarly journals Πρόγνωση ασθενών με κακοήθεια που εισάγονται στη μονάδα εντατικής θεραπείας

2013 ◽  
Author(s):  
Σουσάνα Ανίσογλου
Keyword(s):  
Standard Deviation ◽  
Performance Status ◽  
T Test ◽  
Apache Ii ◽  
Saps Ii ◽  
Student’S T ◽  
Student’S T Test

ΣΚΟΠΟΣ: Η συλλογή, ανάλυση και επεξεργασία στοιχείων ογκολογικών ασθενών που νοσηλεύθηκαν στη Μονάδα Εντατικής Θεραπείας (Μ.Ε.Θ.) και η συσχέτισή τους με συγκεκριμένους πιθανούς παράγοντες κινδύνου .ΥΛΙΚΟ: Πρόκειται για μία προοπτική μελέτη παρατήρησης (prospective observational) σε δείγμα 125 ογκολογικών ασθενών που νοσηλεύθηκαν στη Μ.Ε.Θ. κατά την τελευταία διετία.ΜΕΘΟΔΟΣ: Αξιολογήθηκαν επιδημιολογικοί, κλινικοί και λειτουργικοί παράγοντες. Ειδικότερα ελέγχθηκαν η πρωτοπαθής νεοπλασματική νόσος, η ηλικία, η παρουσία στεφανιαίας νόσου, χρόνιας αποφρακτικής πνευμονοπάθειας, σακχαρώδους διαβήτη, νεφρικής ανεπάρκειας, ο δείκτης μάζας σώματος, η εφαρμογή χημειοθεραπείας ή και ακτινοθεραπείας, η διάρκεια νοσηλείας, τα score βαρύτητας (APACHE II, SAPS II, SOFA) και η έκβαση (εξιτήριο ή θάνατος) και έγιναν συσχετίσεις με τα προηγούμενα στοιχεία. Χρησιμοποιήθηκε το στατιστικό λογισμικό πακέτο SPSS 17.0 (SPSS, Chicago, IL, USA) για Windows. Οι συνεχείς μεταβλητές παρουσιάζονται ως μέσοι όροι + τυπική απόκλιση (mean + standard deviation). Για τη σύγκριση των μέσων όρων μεταξύ δύο ομάδων έγινε χρήση του student’s t-test, εφόσον οι μεταβλητές ακολουθούσαν την κανονική κατανομή και του Mann-Whitney U test στην αντίθετη περίπτωση. Για την ανάδειξη συσχετίσεων μεταξύ ποιοτικών μεταβλητών έγινε χρήση του x2 test.ΑΠΟΤΕΛΕΣΜΑΤΑ: Η θνητότητα ανήλθε στο 48.8%. Στατιστικά σημαντικοί παράγοντες κακής έκβασης κατά την εισαγωγή του ασθενούς στη ΜΕΘ ήταν τα score βαρύτητας (APACHE II, SAPS II, SOFA), το πτωχό performance status και τα συνυπάρχοντα σοβαρά νοσήματα. Στατιστικά σημαντικοί παράγοντες κακής έκβασης κατά τη διάρκεια νοσηλείας του ασθενούς στη Μ.Ε.Θ. ήταν η διάρκεια του μηχανικού αερισμού, η χρήση αγγειοσυσπαστικών, η πολυοργανική ανεπάρκεια και η σηπτική κατάσταση. Από τις εργαστηριακές εξετάσεις στατιστικά σημαντικές ήταν ο χαμηλός αριθμός αιμοπεταλίων και η θετική αιμοκαλλιέργεια. Ο στατιστικός έλεγχος αξιολόγησης κατά Hosmer Lemeshow παρά τον σχετικά μικρό αριθμό του δείγματος επιβεβαίωσε τη χρησιμότητα των APACHE II, SAPS II, SOFA ως προγνωστικών μοντέλων.ΣΥΜΠΕΡΑΣΜΑΤΑ: Η πρόγνωση ογκολογικών ασθενών που εισάγονται στη ΜΕΘ είναι μέτρια. Υπάρχουν σαφείς προγνωστικοί παράγοντες κινδύνου που μπορούν να συνθέσουν ένα είδος προγνωστικού μοντέλου, ωστόσο απαιτούνται περαιτέρω πολυκεντρικές μελέτες με προοπτικό χαρακτήρα σε μεγαλύτερο αριθμό ασθενών.

On the Use of Student's t-Test in an Asymmetrical Population

Biometrika ◽  
1949 ◽  
Vol 36 (3/4) ◽  
pp. 426
Author(s):  
S. G. Ghurye
Keyword(s):  
T Test ◽  
Student’S T ◽  
Student’S T Test
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